Lacey Spears listens as the jury foreman reads her guilty verdict of second-degree murder in the death of her son. The verdict came March 2, 2015, at the Westchester County Courthouse.(Photo: The Journal News, file)Buy Photo

New York's highest court has declined to hear the appeal of Lacey Spears, who was convicted of murdering her 5-year-old son, Garnett, by poisoning him with salt.

Spears' lawyers wanted the Court of Appeals to take the case after a state appellate court in October upheld the conviction. It is extremely rare for the court to accept such appeals — in 2016, it did so less than 2 percent of the time — and no reason was given for last week's decision.

“I am extremely pleased that the state’s highest court has declined to review Lacey Spears’ murder conviction, thus bringing greater finality to the jury’s judgement and, most importantly, justice for Garnett,” Westchester County District Attorney Anthony Scarpino said in a statement.

Spears was sentenced to 20 years to life in prison in 2015 after a jury convicted her of second-degree murder under the theory that she showed a depraved indifference to Garnett's life. She is incarcerated in the state's prison for women in Bedford Hills.

The Appellate Division, 2nd Department, three months ago found that Spears' sentence was not excessive and that, while the trial judge mistakenly allowed a Wikipedia article about hypernatremia into evidence without authentication, it was a "harmless" error.

"Of course it is extraordinarily disappointing that the Court of Appeals has decided not to permit Lacey to file an appeal," her lawyers, Stephen Riebling and David Sachs, said in a statement Monday. "We feel very strongly that if the Court of Appeals had permitted the appeal and reviewed the full merits of the case and the law, that Lacey's conviction would have to be reversed. At this juncture, all of Lacey's legal remedies will be explored, including appealing to the federal court."

Garnett Spears lived with his mother in Chestnut Ridge. He died Jan. 23, 2014, of hypernatremia, or elevated sodium levels that caused his brain to swell. He had been airlifted to Westchester Medical Center four days earlier from Nyack Hospital after elevated sodium levels were discovered and he was no longer breathing on his own.

Garnett Spears with his mother, Lacey, in Nyack Hospital days before his death from salt poisoning.(Photo: File photo)

His mother had taken him to Nyack Hospital claiming he had been suffering seizures, the latest in a myriad of medical problems that she posted about on social media.

A video camera installed to record the physical symptoms of seizures showed her twice taking her son to the bathroom with a cup and his feeding tube. After each visit, Garnett suffered headaches and diarrhea and a blood test showed the elevated levels of sodium.

Prosecutors contended that Spears had often sickened her son to satisfy her own need for attention.

Decisions on whether to accept appeals are made by individual judges of the court. In Spears' case it was rejected by Associate Justice Jenny Rivera. There was no need for Chief Justice Janet DiFiore, who was Westchester's district attorney when Spears was prosecuted, to recuse herself.